Thank you. She is a very sweet horse. What she has is cancer of the 3rd eyelid. Thankfully it is a slow growing cancer and we believe we have caught it in time. They will put her under local anesthetic and carefully remove the inner eyelid. As far as drying out, the vet has told me no ill side effects. She will still be able to close her eyes. Here is a link to the surgery and process of removing this kind of tumor:
If you have a weak stomach, be advised. It could be hard to watch.
And here are pictures of hers.